Department of Electrical and Computer Engineering, Cleveland State University, Cleveland, OH 44115, USA.
Biosens Bioelectron. 2011 Mar 15;26(7):3386-90. doi: 10.1016/j.bios.2011.01.009. Epub 2011 Jan 13.
Detection of analytes on the zepto-molar (10(-21) M) level has been achieved using a field-effect bio-detector. By applying a gating voltage to enzymes immobilized on the working electrode of the detector, amplification of the biocatalytic current was observed. The amplification is attributed to the modification of the tunnel barrier between the enzyme and the electrode by the gating voltage-induced electric field which exists at the solution-electrode interface. The detection was demonstrated with the glucose oxidase (GOx)-glucose and alcohol dehydrogenase (ADH)-ethanol biocatalytic systems. Glucose at zepto-molar level was detected with zepto-molar detection resolution. Equivalently, 30 glucose molecules present in the sample were detected and the detection system responded distinctively to the incremental change in the number of glucose molecules in unit of 30 molecules. The enzyme's biospecificity was also preserved in the presence of the applied field. We present possible processes that could give rise to the electrical charges required to produce the observed current level.
使用场效应生物探测器已经实现了对纳摩尔（10(-21) M）水平的分析物的检测。通过向固定在探测器工作电极上的酶施加门控电压，观察到生物催化电流的放大。这种放大归因于门控电压诱导的电场对酶和电极之间隧道势垒的修饰，该电场存在于溶液-电极界面处。该检测通过葡萄糖氧化酶（GOx）-葡萄糖和醇脱氢酶（ADH）-乙醇生物催化系统进行了演示。纳摩尔水平的葡萄糖具有纳摩尔检测分辨率。同样，可以检测到样品中存在的 30 个葡萄糖分子，并且检测系统对单位为 30 个分子的葡萄糖分子数量的增量变化做出了明显的响应。在施加电场的情况下，酶的生物特异性也得以保留。我们提出了可能产生产生观察到的电流水平所需的电荷的过程。
